# CVE-2026-73974 — Linuxfabrik monitoring-plugins

> As of 2026-08-19, CVE-2026-73974 is a MEDIUM-severity vulnerability in Linuxfabrik monitoring-plugins, CVSS v3.1 5.5, EPSS 0.1% (3.7th percentile). No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-73974 as of 2026-08-19; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-08-19

## What is CVE-2026-73974?

linuxfabrik-lib provides Python modules for database access, caching, shell execution, and API integrations, and Linuxfabrik Monitoring Plugins uses its shared testing helper across check plugins. Prior to linuxfabrik-lib 6.1.0 and Linuxfabrik Monitoring Plugins 7.0.0, lib.lftest.test() treated the first or second element of a --test CSV argument as a filesystem path and returned the file contents as simulated standard output or standard error without path confinement. The hidden but production-accessible --test argument was accepted by sudo-authorized plugins, so an attacker controlling the nagios or icinga account could use check-plugins/deb-updates/deb-updates with its default QUERY=1 to disclose every line of a root-readable file. Approximately 22 other plugins exposed filtered content or a root file existence and readability oracle through the same helper, while check-plugins/network-bonding/network-bonding and check-plugins/openstack-swift-stat/openstack-swift-stat had direct read paths that bypassed the helper. The library fix confines fixture reads to the invoking plugin's unit-test directory and refuses unsafe anchors, and the plugin fix routes the two bypasses through that helper. These issues are fixed in linuxfabrik-lib 6.1.0 and Linuxfabrik Monitoring Plugins 7.0.0.

The record classifies CVE-2026-73974 under weakness classes [CWE-22](https://intel.threadlinqs.com/cwe/CWE-22), [CWE-269](https://intel.threadlinqs.com/cwe/CWE-269). Its CVSS v3 base vector states that the flaw requires local access to the host, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality. 2 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 48 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 5.5 — MEDIUM (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N`)
- **EPSS (FIRST):** 0.1% probability of exploitation in the next 30 days, higher than 3.7% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 2.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-08-18, last modified 2026-08-19

## Is CVE-2026-73974 being exploited?

It currently carries a trending score of 31 in the Threadlinqs vulnerability feed.

## Affected products and versions

- **Linuxfabrik**: monitoring-plugins, lib

Affected software packages:

- `pip:linuxfabrik-lib` — patched in 6.1.0

## How to fix CVE-2026-73974

Fixed versions are recorded for 1 package: pip:linuxfabrik-lib 6.1.0. No vendor patch reference has been recorded for CVE-2026-73974 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-73974

No threat campaign in the Threadlinqs corpus currently references CVE-2026-73974, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org, NVD, GitHub Security Advisories, FIRST EPSS. Last verified by Threadlinqs on 2026-08-19. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [github.com](https://github.com/Linuxfabrik/monitoring-plugins/security/advisories/GHSA-rh9c-rqvg-f7pr)

**Other references**

- [github.com](https://github.com/Linuxfabrik/lib/commit/d665042c55fae83a295ebc0023e8b77f6c473a28)
- [github.com (f6680a9e4b39569f318feefdb2f51e5d18c7dad5)](https://github.com/Linuxfabrik/monitoring-plugins/commit/f6680a9e4b39569f318feefdb2f51e5d18c7dad5)
- [github.com (v6.1)](https://github.com/Linuxfabrik/lib/releases/tag/v6.1.0)
- [github.com (v7.0)](https://github.com/Linuxfabrik/monitoring-plugins/releases/tag/v7.0.0)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-73974
Full detection coverage and IOCs for threats exploiting CVE-2026-73974 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp